Differential stage lift flow device



April 4, 1944. A. BOYNTON DIFFERENTIAL STAGE LIFT FL OW DEVICE FiledDec. 8, 1939, 2 Sheets-Sheet l N 0 T N V 0 5 n E D N X t L A Fig 5.

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April 4, 1944.

A. BOYNTON DIFFERENTIAL STAGE LIFT FLOW DEVI CE Filed Dec. 8, 1939 2Sheets-Sheet 2 ATTORNEYS.

Patented Apr. 4, 1944 UNITED STATES PATENT FFICE 2,345,865 7DIFFERENTIAL STAGE LIFT FLOW DEVICE- Alexander Boynton, San Antonio,Tex. Application December 8, 1939, Serial No. 308,317

g 8 Claims. (01.137-153) My invention relates to stage lift flowingdevices for expelling liquids from wells, especially oil wells.

The principal objects are to provide: (1) a valve that will meter thepressure fluid to the well liquid in proportion to the volume of suchliquid being lifted; (2) means for holding the valve closed againstmomentary fluctuations in the differential; (3) means for admittingpressure fluid into the device in such manner as will not cut nor abradethe valve mechanism; (4) construction which permits adjustments andreplacements to be easily and quickly made; and (5) a device for suchpurposes which will be durable in operation and inexpensive tomanufacture.

For these purposes, I employ a differentially operated combinationsleeve and poppet valve having a shank extending through a meteringchamber. I also employ a latch and/0r piston and check valve operable byan extension of the valve member.

The above and other objects are attained by mechanism described in thisspecification and illustrated by the accompanying drawings, in whichFig. 1 is a longitudinalsection through the preferred embodiment.

Fig. 2 is a cross section on the line 22, Fig. 1.

Fig. 3 is a cross section on the line 33, Fig. 4.

Fig. 4 is a partial longitudinal section through a-slightly modifiedform of pressure fluid intake and metering chamber showing the pressurefluid valve closed and the latch engaged.

Fig. 5 is a cross section on the line 5-5, Fig. 1. i

Fig. 6 is a cross section on the line 6-6, Fig. 1.

Fig; 7 is a cross section on the line 1-7, Fig. 1.

Fig. 8 is a cross section on the line 8-8, Fig, 1.

Fig. 9 is a cross section on the line 9-9, Fig. 1.

Fig. 10 is a cross section on the line |0|0 Fig. 1.

Fig. 11 is partially a longitudinal section and partially an outsideview of a further modification of the invention.

Fig. 12 is a cross section on the line l2-I2, Fig. 11.

Fig. 13 is a cross section on the line l3-l3, Fig. 11.

Fig. 1g is a cross section on the line |4-I4, Fig. 11.

Similar characters of reference are employed to designate similar partsthroughout the several views. 1

In Fig. 1 the nipple l is adapted to .be'threadedly joined into the'wel1 tubing string. Over this nipple the upper sleeve 2, having theprojection 2a, is secured by the welds 2b. The lower sleeve 3, havingthe projection 3ais secured over the nipple l by the welds 3d and 3e.

The valve seat member 5 has threaded connection within the projection 3aand with the? lower end of the shell 4. The cover cap l4, ha,vingarod-like upper extension I4d threadedly' connected into the projection2a-of-the-member 2, has its lower expanded shell engaged over thebushing l3, which bushing is threadedly engaged within the shell 4. v

In assembling, the member 14' is screwed upward within the-projection 2wfar enoughto allow the. connected members 4- and 5 to be screwed intothe projection 3a. 'Then the member I 4 is screwed downward until itslower shell firmly engages over the upperend of the bushing l3. In thismanner theshell 4 is secured in alignment with the nipple 1.; g r i iThe head lb of the valve-rod 10 is yieldably positioned within the upperend of the metering chamber 4a by the engagement of the upper tubularextension lie of the piston I upon the nether side of the fins [3a ofthebushing I 3-. This engagement is caused bythe coiled spring 9 preferablyinstalled under some compression andhaving its upper extremity engagedunder the piston II and its lower extremity engaged upon the ballroof 1. V a

The ball floor 6 maybe pressed into the shell 4 and landed upontheslight internal annular shoulder 4c. The latch balls 8 are urged againstthe valve rod ID by the inner inclined surfaces of the members 6 and-Timparting the force of the spring 9. These balls are adapted to engageupon the latching surface of the restricted die ameter lflc of the rod[0 when .the valve lila is engaged upon-its seat 5c of the member 5. I

The untapered portion 521 of the latter member and hefl similarportionAb of.the member '4 preferablyv should be of the same length asthe enlarged, straight portion Illb of the rod iii. The confrontingmetering chambers 4a and 5a preferably are flared as shown for thepurpose of admitting a governed volume of pressure fluid into theeduction tube, the larger -volume preferably being admitted atapproximately one half of the difierential force required to seat-thevalvelfla. i

The piston ll, closely slidable within the. shell 4, may have aleak-proof engagement within this shell by means of the ring I2 whichmay be of leather or may be a series of metallic rings. The centralopening Ho and the cross bores II I) admit pressure fluid to expand thering I2 against the shell 4.

It will be observed that the pressure fluid actuates the piston I I byentering the upper end of the shell 4 via the openings Mo and I4!) andthe chamber Ma.

The pathof the pressure fluid into the tubing is out of the annularspace between the well casing and the tubing via the openings 4d, thechamber lie, the metering chambers 4a, 5a, the opening 5d, the chamber30, and the aligned openings 3b and I a.

Falling slugs of well liquid frequently produce areas of false lowdifferentials "within the eduction tube. These disturbances aretemporary, but frequent, and their efiect is to cause ungoverneddifferentially operated valves to fly open and admit excessive volumesof pressure fluid during the flowing operation.

The latch balls 8 engaging upon the latching surface like prevent thevalve 1 a from responding to such sudden disturbances in thedifferential. Preferably the latch should be adjusted to hold one fourthtoone half of the unseating force exerted by the spring 9-. The latchmay be adjusted by means of the nut lid. The threads shown in the upperend of the opening I Ia of the plunger extension II'c are for connectinga testing tool employed in "adjusting the latch.

A dashpot timing means within the chamber 14a of the member I4 is alsoprovided to delay the opening of the valve Illa. The spring supportbushing l5; threadedly engaged within the cover cap M, forces thesensitive spring IE to engage lightly under the wings Ila of the valveIT-. This valve has slight clearance, such as one or two thousandths ofan inch, with the opening Mb; the fins IIa extending upward to providesuch clearance. Whenthevalve a is traveling toward its seat 50, pressurefluid is drawn into the chamber I M and into the chamber 4f above thepiston (see Fig. 4-), through the cross, bores I40 and the opening I ib;but when the valve Illa recedes from its seat, the pressure fluidentrapped between the piston II and the check valve I1 will escape veryslowly through the slight clearance between the valve I I and the seatfrom which it is held slightly removed bythe wings Ila, as stated. Theclearance between the valve I1 and its proximate seat may be varied'toprovide the proper time element in thev opening of the valve I 0a, suchas will prevent that valve from being actuated by falsedifierentials,

The openings 417., being much smaller than the metering-chambers and theopenings 5d, 3b, and la, it is apparent that the pressure under thepiston I I will be less thanthe pressure above it. This lesser pressureis communicated from the chamber 46 through the slight clearance betweenthe rod I0 and the members 6 and I.

The pressure fluid intake openings, 4d are inclined toward the wall ofthe chamber 4e in order to prevent abrasive substances frequentlypresent in pressure fluidfrom abrading the valve rod' It (see Fig. 5). I

Fig. 4, illustrating a slightly .modified form from Fig. i, has thenipple I8 threadedly joined to the members 3a and I9, and has formedwithin it the metering chamber I8a. The intake nipple I9 has the intakeports I9a confronted by the annular extension I81) of the member I8.

This extension operates as a baffle to shield the rod In from theabrasive action of the pressure fluid. When the valve Illa is seated,the latch balls 8 are engaged upon the latching surface Mic.

The space M in Fig. 4 will be filled with pressure fluid entrappedbetween the check valve ll (see Fig. 1) and the piston II where it willact to retard the opening of the valve IIJa, as was explained inconnection with Fig. 1.

The parts bearing the same reference characters in Figs. 1 and 4 will beunderstood to be the same in purpose.

In Fig. 11, illustrating a further modification, the shell 20 isthreadedly connected into the projection 3d and has its upper endthreadedly engaged with the cap having a countersink in its upper endinto which the stud 21 is engaged in order to secure the shell 20aligned with the tubing nipple I.

The plunger 2.2 ha threaded connection with the rod 28 which rod issimilarly engaged with the piston 24, having a close sliding fit withinthe shell 29. The locking screw 25 secures the rod 28 in pro-perposition within the piston for the latch balls 8 to engage within thelatching surface 28a when the valve 220 of the plunger 22 is engagedupon the seat 2342 of the member .23.

The spring 9, installed under som compression, is engaged between theball roof I and the piston '26 and normally urges this piston to engageupon the lower end of the cap 26.

The packing I2 is urged against the shell '20 by pressure fluidcontacting its inner surface via the recess 2% and the openings 24b. Thevalve seat member 23 may be pressed into the shell 20 and landed uponthe internal annular shoulder 23c. The member 21 and the ball floor 6may be fitted closely within this shell but the ball roof I and theshell should have some clearance between them in order that the latchaction will be free.

The tubular extension 2Ic of the member 2I supports the ball floor 6 andhas the openings 2Ib out of alignment with the intake openings Zila inorder to provide a bafile to protect the metering pin 2211 from beingabraded by foreign substances in the pressure fluid.

The metering pins 22a and 22b of the plunger 22 are convexly tapered inopposite directions, as appears in Fig. 11. The lower metering pin 22!)has diminishing clearance within the central opening 231) as the valve220 approaches the seat 23a, while at the same time the upper meteringpin has increasing clearance within the metering sleeve Zia in orderthat the greatest volume of pressure fluid will be admitted into thetubing when the valve 22c is approximately half way of its travel towardthe seat 23a. Manifestly, the taper of these metering pins may be variedand the clearance which they respectively have within the centralopenings through the sleeve 2Ia and the member 23 also may be varied tocorrespondingly increase or decrease the flow of pressure fluid at anygiven diiierential.

, When the valve 220 and the seat 230. are engaged, a considerablevolume of pressure fluid will be trapped between the piston 24 and thecheck valve II, aswas'explained in connection with Fig. 1. Thisentrapped pressure fluid will be discharged slowly past the valve I! anddelay the opening of the valve 22c after the latch springs. The sectionZ2', Fig. 11, is the same as the section 22, Fig. l; likewise thesection 'I'--'I', Fig. 11, is the same as the section 'i--I, Fig. l; butthe members out are not identical; hence both of these sections areindicated as prime in Fig. 11 in order to avoid any possible confusionas to parts. 7

As the piston 24 travels downward, pressure fluid enters the chamber Maand follows the piston via the openings I42: and I40.

In Figs. 1 and 11, the latch consisting of the members 6, 1 and 8 andthe dashpot timing means consisting of the members l5, l6 and H, aresimilar in construction and identical in purpose.

The path of the pressure fluid through the device is out of the annularspace between the tubing and the casing and into the tubing via theopenings 20a and 2| 1), the clearance between the metering pin 22a andthe sleeve 2 la, the chamber Zld, the opening 232), the chambers 20b and3c, and the aligned openings 32) and la.

It will be understood that compressed air or gas, herein referred to aspressure fluid, will be employed as a power means for accomplishing flowof the well liquid through the eduction tube.

The pressure fluid force is constant at any given value thereof. Thespring force is also constant while the force exerted by the upstandingcolumn is variable, depending upon the level where exerted.

The liquid column caused to upstand in the tubing responsive to pressurefluid force in the annular space between the tubing and the casing, willbe referred to as the upstanding column; and the lower liquid level inthe annular space between the tubing and the casing will be referred toas the depressed liquid level.

It will be understood further that a portion of the upstanding columnmay be expelled from the well as a slug by admitting pressure fluid intoit near its base or that expulsion of the well liquid will result fromaeration, due to admitting pressure fluid at one or more places in theupstanding column which will be stretched or elongated by expansion ofpressure fluid globules until flow is accomplished thereby.

The difference in pressures obtaining at the same level in the tubingand in the annular space between the tubing and the casing will bereferred to as the difierential, that being the force which actuates thevalves in all forms of this invention.

The devices are connected into the tubing string at intervals which mayvary, 200 to 300 feet being i the usual spacing. This spacing,ordinarily, should be determined by the diiferential force required toseat the pressure fluid valves.

Preferably, the per square inch diiferential force required to seat thevalves should be equal to. or somewhat greater than, the per square inchweight of well liquid between any two devices. Such adjustment willalways cause a lower valve to be uncovered by the receding well liquidbefore the valve next above it will be closed.

The diameter of the piston being many times greater than the diameter ofthe valve that it controls, as shown, it is evident that the valve willbe actuated in its movements and seated by a much greater force than canbe employed to actuate and seat the usual valve which has the sameseating areas as that employed to contact the seating force.

The value of the pressure fluid should be at least two or three timesthe diilferential force required to seat the valves, and may be muchgreater.

In Fig. 16, illustrating the installation plan in a well, the casing 29has the tubing 30 suspended centrally within it. The casing head 32accomplishes a hermetic seal between the tubing and the casingproximately above the ground surface 35.

The flow devices 3| are spaced at intervals which ordinarily may varybetween 200 and 300 feet, as stated. The anchor string 38 may extend tothe bottom of the well 36 to support part of the weight of the tubing.The intake nippl 3! may be joined between the tubing and the anchorstring.

The formation 40 discharges its production into the well casing 29 viathe gun perforations 39.

One side of the casing head is shown closed by the bull plug 34.Pressure fluid may be supplied into the annular space 44 from the pipeline 33 which may be connected with a compressor plant or a gas line.Manifestly, if the well produces enough gas to flow it, the opening inthe casing head shown occupied by the pipe line 33 may be closed by aplug. The tubing 30 may extend to a flow tank or separator. T

The normal liquid level in both the tubing and the casing is assumed tobe standing at 4!.

Now, to initiate flow, turn pressure fluid from the pipe line 33 intothe annular space 44, the line 30 being open. The valve in each devicewill quickly close, due to increasing pressure in the annular space 44.The well liquid exterior of the tubing will soon be depressed to 42 andwill upstand in the tubing to a level indicated at 43. The flow devicenearest to the base oi the upstanding liquid column then will beintaking pressure fluid. The device next above will be closed orclosing, depending upon the distance and weight of the well liquidbetween it and the base of the upstanding column.

Each device uncovered by the receding liquid level 42 will be open andintaking pressure fluid. while the one next above will be closing. Thisoperation continues as the well liquid is expelled by stages in a mannerwell known to the art.

It is apparent that the device described as the preferred embodiment ofthe invention may be inverted from the position shown and operateequally well by virtue of inherent operating characteristics of thedevice.

The invention as herein illustrated and described is manifestly subjectto many changes in construction and arrangement of parts which willremain within the scope and purpose of the stated objects and appendedclaims.

The invention claimed is:

1.. A well flowing device comprising a valve body having apassage'waywith spaced inlet and outlet openings and a valve seatproximate the one end thereof and leading from the exterior to theinterior of the body, a metering chamber in the passageway intermediatesaid openings, a valve assembly movable in and adjacent to thepassageway. said assembly including a valve member in the passageway, apiston in an opening adjacent the passageway, there being a pas sage tothe side of the piston opposite said openings to admit fluid to thepiston, a piston rod connecting the valve member and piston, aperipheral groove in said piston rod, a latch assembly surrounding thepiston rod and including a plurality of latch balls adapted toreleasably engage the piston rod when the valve member moves to apredetermined position, and a spring in the passageway engaging thepiston and latch assembly to normally urge the valve assembly away fromsaid seat and to urge' the latch balls to latching position within saidgroove.

2. A well flowing device comprising a body, a passageway for pressurefluid through a portion of said body, inlet and discharge openings insaid passageway, said inlet openings communicating between saidpassageway and the exterior of said body, and said discharge openingcommunicating between said passageway and the interior of an othermember of said body, a metering chamber within said passagewayintermediate said intake and discharge openings, a valve seat proximateone end of said metering chamber, a valve normally positioned withinsaid passageway and proximate the opposite end of said. metering chamberrelative to said valve seat, a rod connected to said valve, a pistonconnected to said rod, said piston being slidable in a member of saidbody and having a peripheral groove containing packing and also havingan extension with an axial opening communicating with cross boresleading to the inner surface of said packing, a check valvein said body,said valve having its surface cut by a slot, openings communicatingbetween said check valve and the exterior of said body, a spring in saidbody resiliently urging said check valve upon its seat, another springin said body, said spring being adapted to urge the piston and valveaway from said seat. 1

3. A well flowing device comprising a body, a passageway for pressurefluid through a portion of said body, inlet and discharge openings insaid passageway, said inlet openings communicating between saidpassageway and the exterior of said body and said discharge openingcommunicating between said passageway and the interior of.an

other portion of said body, a metering chamber within said passagewayintermediate said intake and discharge openings, a valve seat proximateone end of said metering chamber, a valve normally positioned withinsaid passageway and proximate the opposite end of said metering chamberrelative to said valve seat, a rod connected to said valve and having anannular recess adapted to be engaged by a latch, a piston connected tosaid rod, said piston being slidable in a member of said body and havinga peripheral groove containing packing and also having an extension withan axial opening communicating with cross bores leading to the innersurface of said packing, a latch in said body, said latch being adaptedto engage balls within said annular recess of said rod, a spring in saidbody, said spring being adapted to urge the latch to close upon saidrod, and to urge the piston and 7 valve away from said seat.

4. A nipple adapted to be joined into the tubing of a well, a tubularshell assembly adapted to be joined laterally with and parallel to saidnipple, means for securing such joinder, a passageway for pressure fluidthrough a portion of said shell assembly, inlet and discharge open ingsin said passageway, said inlet openings communicating between saidpassageway and the exterior of said shell assembly and said dischargeopening communicating between said passageway and the interior of saidnipple, an annular bafile member opposite said inlet openings, ametering chamber within said passageway intermediate said intake anddischarge openings, an annular valve seat proximate one end of saidmetering chamber, a valve normally positioned within said passageway andproximate the opposite end of said metering chamber relative to saidvalve seat. a rod connected to said valve and having an annular recessadapted to be engaged by a latch, a piston connected to said rod, saidpiston being slidable in said shell assembly and having a peripheralgroove containing packing and also having an extension with an axialopening communicating with cross bores leading to the inner surface ofsaid packing, a bushing in said shell assembly, said bushing havingwings adapted to be engaged by said extension of the piston, a checkvalve in said shell assembly, said valve having its surface cut by aslot, openings communicating between said check valve and the exteriorof said'shell assembly, a spring in said shell assembly resilientlyurging said check valve upon its seat, a latch in said shell assembly,said latch being adapted to engage balls within said annular recess. ofsaid rod, a spring in said shell assembly, said spring being adapted tourge the latch to close upon said rod and the piston ,to engage saidbushing,

5. A well flowing device comprising a valve body having a throughpassageway, a shell attached to said valve body and having a meteringchamber with spaced inlet and outlet openings communicating with theexterior and interior of the valve body, a piston chamber in the shellcommunicating with said metering chamber, a valve and piston assemblywithin said chambers. said assembly including a piston in said pistonchamber and a valve in said metering chamber intermidate the inlet andoutlet openings, con necting means between said valve and piston, therebeing an opening in the piston chamber beyond the piston relative tosaid valve, a valve seat facing the valve in the metering chamber, andresilient means normally holding the valve and piston assembly in aposition with the valve member in spaced relation to the valve seat. 1

6. A well flowing device comprising a valve body, a shell attachedthereto and having a passageway with spaced inlet and outlet open ingsproximate one end thereof, said body having a through bore and saidopenings and passageway constituting a passage between the exterior andinterior of the body, a piston chamber having communication with saidpassageway, a metering chamber in the passageway intermediate saidopenings, a valve movable within said metering chamber to control thpassage of pressure fluid from the exterior to the interior of the valvebody, a valve seat confronting said valve member in said meteringchamber a piston in said piston chamber, means for connecting said valvemember and piston, a spring within said piston chamber normally urgingthe piston and valve so that the valve is spaced from said valve seat,and means for admitting pressure fluid to the side of said pistonopposite said spring, said last mentioned means including a leaky checkvalve whereby the movement of the piston and valve away from said seatis retarded.

'7. A well flowing device comprising a valve body having a throughpassageway, a shell having a chamber with spaced inlet and outletopenings proximate one end thereof, said openings communicatingrespectively with the exterior and interior of the valve body,saidchamber comprising oppositely flared walls having an annular valveseat about the outlet opening, a valve member movable within saidchamber to control the passage of fluid therethrough and to move intoengagement with said seat to close the passage, and means resilientlyholding the valve in spaced relation with its seat and operable by thedifferential pressure between said chamber and the exterior of the valvebody to control the flow of pressure fluid to the interior.

'Of the valve body.

8. A well flowing device comprising a valve body having a throughpassageway, a shell having a chamber with spaced inlet and outletopenings proximate one end thereof, said openings communicatingrespectively with the exterior and interior of the valve body, saidchamber comprising oppositely flared walls having an annular valve seatabout the outlet opening, a valve member movable within said chamber tocontrol the passage of fluid therethrough and to 10 move into engagementwith said seat to close the passage, means resiliently holding the valvein spaced relation with its seat and operable by the differentialpressure between said chamber and the exterior of the valve body tocontrol the flow of pressure fluid to the interior of the valve body,and means for releasably latching the valve in engagement with saidseat.

ALEXANDER BOYNTON.

